Migrate gbfs java model to mobilitydata package

[testower]

Migrates the gbfs java model package to the one hosted by mobilitydata. Entur's package is deprecated. This PR involves only changing the group id and version in the pom file, and updating the package import paths.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 68.38%. Comparing base (39a7270) to head (ca07e9a).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## dev-2.x #5873 +/- ## ========================================== Coverage 68.37% 68.38% + Complexity 16680 16679 -1 ========================================== Files 1914 1914 Lines 72658 72658 Branches 7453 7453 ========================================== + Hits 49683 49684 +1 + Misses 20418 20417 -1 Partials 2557 2557 ```

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[leonardehrenfried]

For everyone looking for the new location of the code: https://github.com/MobilityData/gbfs-json-schema/tree/master/models/java

[testower]

Do we need anymore approvals or can I merge?

[leonardehrenfried]

Go ahead and merge.

[leonardehrenfried]

We usually give the person that opened the PR the satisfaction of clicking the merge button.